import java.io.*;
import java.util.Scanner;

public class Demo12 {
    public static void main(String[] args) {
        // 1. 输入必要的信息
        Scanner scanner = new Scanner(System.in);
        System.out.println("请输入要复制的文件路径: ");
        String srcPath = scanner.next();
        System.out.println("请输入要复制到的目标路径: ");
        String destPath = scanner.next();

        // 2. 验证上述路径是否合法.
        File srcFile = new File(srcPath);
        if (!srcFile.isFile()) {
            System.out.println("输入的要复制的文件路径非法!");
            return;
        }
        File destFile = new File(destPath);
        if (!destFile.getParentFile().isDirectory()) {
            System.out.println("输入的要复制到的目标路径非法!");
            return;
        }

        // 3. 读写文件
        try (InputStream inputStream = new FileInputStream(srcFile);
             OutputStream outputStream = new FileOutputStream(destFile)) {
            while (true) {
                byte[] bytes = new byte[1024];
                int n = inputStream.read(bytes);
                if (n == -1) {
                    break;
                }
                outputStream.write(bytes, 0, n);
            }
        } catch (IOException e) {
            throw new RuntimeException(e);
        }
    }
}
